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First, I am not doing fail-over. I want to be able to add another ISP link using a HWIC-4ESW.

Equipment: Cisco 3825(1GB ram, 2GB flash, IOS 15.4 Advanced Enterprise services) with HWIC-4ESW available.

Currently doing Router on a stick with Gi0/1 to a managed switch with current ISP on Gi0/0. I need to add a second link to the same ISP(they dont provide any more bandwidth per link, other ISP's in area do not provide anything better either). My ISP does not allow bonding on these links, but does allow load balancing if I do it on my router.

I have a few options: 1) use a switch to join both ISP provide modems before the router. (not the best solution, but workable) 2) use a HWIC-4ESW I have laying around and try to use it. ( prefered method as I have the HWIC on hand) 3) spend the money on a HWIC-2FE and use layer3 routing. (the best way, but also costly. Will solve the issue now but I will have to buy more hwic-2fe's as I add) 4) Use the Router on a stick config to provide layer3 routing to the other vlans and control access using ACLs. (also workable, but not prefered as ISP traffic is not and can not be tagged or it gets dropped. 5) use a linux server to provide balancing and aggregation then forward to router (uses 2 of my limited static IP addresses (/29))

My question is if I can get option 2 to work and how I would set it up? If option 2 will not work please make suggestions based on the other options available.


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Is your ISP routing your internal IP space to you, or are you NAT-ing to the single IP they give you on your uplink? – cpt_fink Mar 11 '13 at 2:40
Doug, Is the second ISP link just a redundant link to the same ISP router? i.e. you are going to be using your current public IPs on the second link? – GerryEgan Mar 11 '13 at 18:01
Are you terminating PPPoE/PPPoA on your router, or on your modems and they are passing your /29 to your router? – jwbensley Jun 19 '13 at 19:08
ok, been very busy and havent been back to this site in a long time. I am still looking for a good soluton, so here is my answers to the above and what I have done since: – Doug Jun 2 '14 at 2:19
My ISP provides a /29 from their public IP block. They route but do not do much else, best I could get out of them is that my IP's are not blocked but that doesnt mean anything on how my IPs are transported from there pop to their gateway. No, I am not building a redundant link. My goal is to provide aggregate bandwidth and to be able segregate client bandwidth if required. – Doug Jun 2 '14 at 2:37

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